Focus fader with a plurality of optocouplers

ABSTRACT

The apparatus is a cross fader with a plurality of optocouplers wired in parallel electrical relationship with each other. A slider interrupts the light signal of at least one of the optocouplers and the resultant information is communicated to a chip which determines the position of the slider and thereby calculates the resultant mix of first and second electronic audio signals to derive a third electronic audio signal which is the output signal.

[0001] The present application is a continuation-in-part of U.S. patent application Ser. No. 09/634,410 entitled “Focus Fader with Dual Optocouplers” filed on Aug. 9, 2000, the disclosure of which is hereby incorporated by reference.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] This invention pertains to a cross fader with a plurality of optocouplers, which can be used in a DJ (disk jockey) mixer or as a replacement cross fader for a DJ mixer.

[0004] 2. Description of the Prior Art

[0005] In the prior art, cross faders have used resistive components to allow a user, such as a disk jockey, to cut or short out a first signal from a respective channel of audio signal, while allowing the opposite channel of signal to pass. However, such resistive cross faders have been deficient with respect to noise, wear characteristics and lack of complete cutting of the respective signal.

[0006] Moreover, while the cross fader with dual optocouplers of the parent application has been found satisfactory, some users may prefer a more defined roll-off curve to the fader action.

OBJECTS AND SUMMARY OF INVENTION

[0007] It is therefore an object of the present invention to provide a cross fader which has improved characteristics with respect to noise.

[0008] It is therefore a still further object of the present invention to provide a cross fader which has improved characteristics with respect to wear.

[0009] It is therefore a still further object of the present invention to provide a cross fader which has improved characteristics with respect to the degree to which the signal is cut.

[0010] It is therefore a still further object of the present invention to provide a cross fader which is mechanically and electronically compatible with existing equipment.

[0011] It is therefore a final object of the present invention to provide a cross fader with improved definition in the roll-off curve of the fader action.

[0012] These and other objects are attained by providing a cross fader which uses a plurality of optocouplers wired in parallel with other. A blade shutter passes between the operational slots of the optocouplers. A slider is mechanically coupled to a knob on the outside of the cross fader so that the operator can move the slider to interrupt the light path in selected optocouplers in the plurality. The information regarding which optocoupler light path is interrupted is communicated to a chip which thereby calculates the position of the slider and likewise calculates the desired mix between the first and second input electronic audio signals. The output electronic audio signal is thereby calculated using this information.

[0013] The optocouplers are mounted on a p.c. board for ease of assembly. Likewise, the entire mechanism is mounted to a mounting plate for ease in replacement and securing to the frame of the disk jockey mixer.

DESCRIPTION OF THE DRAWINGS

[0014] Further objects and advantages of the invention will become apparent from the following description and claims, and from the accompanying drawings, wherein:

[0015]FIG. 1 is a perspective view of the circuit board (or P.C. board) and interior of the cross fader of the present invention.

[0016]FIG. 2 is a schematic of the circuit board (or P.S. board) of the cross fader of the present invention.

[0017]FIG. 3 is a top plan view of the face plate of the cross fader of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0018] At the outset, the disclosure of U.S. patent application Ser. No. 09/634,410 entitled “Focus Fader with Dual Optocouplers” filed on Aug. 9, 2000 is hereby incorporated by reference.

[0019] Referring now to the drawings in detail wherein like numerals refer to like elements throughout the several views, one sees that FIG. 1 is a perspective view of the circuit board (or P.C. board) 112 and interior of the cross fader 100 of the present invention while FIG. 2 is a schematic of the circuit board 112. Slider 114 moves between a plurality of ten optocouplers 116, 117, 118, 119, 120, 121, 122, 123, 124 and 125 wired in parallel electrical relationship with each other. The ten optocouplers are powered through electrical terminals 102, 104. The various spaces of the ten optocouplers through which the light paths traverse are aligned to form a path 127 for slider 114. Depending upon the position of slider 114, the light path through at least one of the optocouplers 116-125 is interrupted and this information is communicated to pin nos. 6-13 and 17, 18, respectively, of chip 130 (typically IC 16C54). With this information regarding the position of slider 114, chip 130 calculates a mix of the two input audio signals as received through pins 1 and 2 of chip 130 (as communicated via third and second terminals 135, 134, respectively, of plug 132) and communicates the resultant mix likewise through pin 135 and first terminal 133 of plug 32. Fourth terminal 136 of plug 132 is grounded.

[0020] As shown in FIGS. 1 and 3, slider 114 traverses slot 140 in top plate 142 through a range of positions to interrupt the light paths in the various optocouplers.

[0021] Slider 114 includes a first portion 50 which extends through slot 140 and provides a handle for the user to manually position slider 114. Slider 114 further includes a second portion 152, typically perpendicular to first portion 150, which extends into path 127 formed by the spaces of the various optocouplers 116-125.

[0022] Therefore, to use the cross fader 100 of the present invention, the user provides first and second audio signals through second and third terminals 134, 135 of plug 132. The user then manually, and usually dynamically, varies the position of slider 114 so as to vary the mix of the first and second audio signals in order to obtain a resultant audio signal to be provided through first terminal 133 of plug 132.

[0023] Thus the several aforementioned objects and advantages are most effectively attained. Although preferred embodiments of the invention have been disclosed and described in detail herein, it should be understood that this invention is in no sense limited thereby and its scope is to be determined by that of the appended claims. 

What is claimed is:
 1. A cross fader including: a device for receiving a first electronic signal and a second electronic signal, said first and second electronic signals representing respective audio signals; a plurality of optocouplers, each optocoupler including a space through which a light beam travels, said spaces of said plurality of optocouplers being aligned to form a path; a slider with a range of travel in said path, said slider interrupting a light beam of selective optocouplers depending upon a position of said slider within said range of travel; a processing device receiving information from said plurality of optocouplers thereby determining which of said light beams are interrupted thereby determining a position of said slider, said processing device further determining a mix of said first electronic signal and said second electronic signal dependent upon the position of said slider and output said mix as a third electronic signal.
 2. The cross fader of claim 1 wherein said spaces of said plurality of optocouplers are aligned to form a straight path.
 3. The cross fader of claim 2 wherein said series of optocouplers are wired in parallel electrical relationship with other.
 4. The cross fader of claim 3 wherein said slider includes a first portion which extends through a slot in a plate and includes a handle for manual use, and which further includes a second portion, perpendicular to said first portion, which extends into said spaces of said plurality of optocouplers. 